           (.size right)
           (.stored-at right)
           (.content right)
-          (not-empty (merge (._meta left) (._meta right)))
-          0))
+          (not-empty (merge (._meta left) (._meta right)))))
 
 
 (defn wrap-content


  (hashCode
    [this]
    (let [hc _hash]
      (if (zero? hc)
        (let [hc (hash [(class this) id size])]
          (set! _hash hc)
          hc)
        hc)))


  java.lang.Comparable

   (when-not content
     (throw (ex-info "Block must have a content reader"
                     {:id id, :size size, :stored-at stored-at})))
   (Block. id size stored-at content nil)))


(defn load-block
